A fluid operated actuator for operating a valve between a closed condition and an open condition.
In the prior art it is old to provide an actuator having a piston with plunger mechanism attached thereto to move therewith for flexing the diaphragm of a low pressure valve for moving a valve seat to a valve closed condition and to provide a low pressure valve with a piston resiliently retained in a position that the valve seat is retained in a valve closed position until fluid under pressure is applied for moving the piston against a spring so that the valve diaphragm flexes under the action of the valve seat spring acting against the valve seat to move the seat to a valve open condition. Further it is old to provide a relatively large actuator for operating a high pressure valve between open and closed conditions.
In U.S. Pat. No. 2,618,458 to Fosbender an external eccentric (cam) is mounted in abutting relationship with a plunger assembly for operating valving structure between a valve open and a valve closed position, a lever being attached to the cam for manually rotating the cam. French Pat. No. 1,060,285 to Henric discloses structure similar to that referred to in the preceeding sentence, other than for not showing a lever. U.S. Pat. No. 4,260,128 to Tito discloses a valve actuator that includes a piston having a segmented skirt provided with teeth that engage teeth of a rotor to rotate the rotor. The rotor engages the stem of a ball valve to rotor the ball valve about the same axis as the axis of rotation of the rotor. In one embodiment of Tito, a pair of springs urge the piston to move in a direction opposite that from which it moved by pressurized air being applied.
In the pneumatic tool art, U.S. Pat. No. 1,142,671 to Carmina discloses a pin being extended into one groove of a valve to prevent axial movement while permitting rotational movement of the valve relative to a nipple and being extendable into a second groove to retain the valve in an open condition; and U.S. Pat. No. 2,224,708 to Van Sittert discloses a piston operated rack engaging a gear to rotate a cam that in turn moves a plunger and the tool that is attached to the plunger.
Also it is old to provide a manually operated control that will fit under the cap of a gas cylinder for controlling flow from the cylinder.
In order to provide a relatively small actuator for controlling a high pressure valve this invention has been made.